Mouth (oral cavity) - commonly known, is the place where your teeth grind and chew food, breaking it into small, manageable pieces.
Mouth physiology is quite complex. It has big muscles for power and small muscles for control.
Chewing Process (Mastication)
The muscles of the mouth move the lower jawbone against the upper jaw and enable crushing of relatively hard food. Chewing causes endocrine glands under the tongue and in the back of the mouth to secrete saliva which performs two essential functions.
Chewing increases the surface area of foods which helps to accelerate the beginning of digestion. Some carbohydrate digestion begins in the mouth, but almost no protein or fat digestion occurs there.
When you are ready to swallow, the tongue pushes a piece of chewed food (a bolus) toward the back of your throat and into the opening of the esophagus.